This invention relates to method and apparatus for processing signals of images such as variable tone images or halftone images.
Dither is a technique for representing the entire gray scale of a picture by picture elements with only two levels, that is, white and black. The level of gray generally depends on the number of white or black dots within a unit small area. Some types of the dither technique use screen dot patterns. Computers are frequently employed in performing such types of the dither technique.